mountain bike rear shock spring calculator

Calculator

Results:

Average Leverage Ratio: —

Recommended Rate: — **lb/in**

Recommended Rate (Metric): — **N/mm**

*Assumes a 60% rear weight bias. Spring rates are rounded to the nearest 25 lb/in.

The Mountain bike rear shock spring calculator made by Rollmassif

MTB Coil Spring Rate Charts by Leverage Ratio (Plain Text)

1. Low Leverage Ratio (LR approx 2.5:1) - For Shorter Travel / Highly Progressive Bikes
  • Calculation Base: LR = 2.5. Sag Target = 30%.
  • How to Calculate Your LR: Rear Wheel Travel (mm) / Shock Stroke (mm)
Rider Weight (lbs)Rider Weight (kg)Recommended Spring Rate (lb/in)Recommended Spring Rate (N/mm)
1305927548
1506832557
1707737566
1908640070
2109545079
23010450088
25011355097
2. Medium Leverage Ratio (LR approx 2.8:1) - Most Common for Enduro/All-Mountain
  • Calculation Base: LR = 2.8. Sag Target = 30%.
Rider Weight (lbs)Rider Weight (kg)Recommended Spring Rate (lb/in)Recommended Spring Rate (N/mm)
1305930053
1506835062
1707740070
1908645079
2109550088
23010455097
250113600105
3. High Leverage Ratio (LR approx 3.2:1) - Common for Downhill/Long Travel Bikes
  • Calculation Base: LR = 3.2. Sag Target = 35%.
Rider Weight (lbs)Rider Weight (kg)Recommended Spring Rate (lb/in)Recommended Spring Rate (N/mm)
1305932557
1506837566
1707742574
1908647583
2109552592
230104575101
250113625110
How to Use These Charts
  1. Find Your Bike's Leverage Ratio (LR): Divide your Rear Wheel Travel (mm) by your Shock Stroke (mm).
  2. Choose the Closest Chart: Select the chart whose LR value (2.5, 2.8, or 3.2) is closest to your bike's calculated LR.
  3. Find Your Weight: Use your fully kitted-up weight to find the corresponding row.
  4. Select Spring Rate: The recommended spring rate is your starting point.